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Conductance through Quantum Dots Studied by Finite Temperature DMRG

Isao Maruyama·Naokazu Shibata·Kazuo Ueda
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Abstract

With the Finite temperature Density Matrix Renormalization Group method (FT-DMRG), we depeloped a method to calculate thermo-dynamical quantities and the conductance of a quantum dot system. Conductance is written by the local density of states on the dot. The density of states is calculated with the numerical analytic continuation from the thermal Green's function which is obtained directly from the FT-DMRG. Typical Kondo behaviors in the quantum dot system are observed conveniently by comparing the conductance with the magnetic and charge susceptibilities: Coulomb oscillation peaks and the unitarity limit. We discuss advantage of this method compared with others.

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Isao Maruyama, Naokazu Shibata, Kazuo Ueda. 2004-06-24. Conductance through Quantum Dots Studied by Finite Temperature DMRG. https://doi.org/10.1143/jpsj.73.434

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